Conveyor assembly

ABSTRACT

A conveyor system is set forth that includes a track having a generally linear section and a generally curved section. The track further includes a guide channel having sidewalls that engage a guide member that is in fixed positional alignment, for example, with a carrier and/or belt. The guide member engages the sidewalls of the guide channel to facilitate guided movement of the carrier and/or belt along the track. The guide member includes a linear portion that is engaged by the track when the guide member is disposed along the linear section of the track while being generally disengaged from the track when the guide member is disposed along the curved section of the track. The guide member further includes a curved section that engages the sidewalls of the guide channel when the guide member is disposed along the curved section of the track. The radius of curvature of the curved portion of the guide member generally coincides with the radius of curvature of the track about a curved portion of the track.

This is a continuation of application Ser. No. 08/282,981, filed Jul.29, 1994, now U.S. Pat. No. 5,460,262.

FIELD OF THE INVENTION

The present invention relates to a conveyor guide assembly. Moreparticularly, the present invention relates to an endless belt conveyorguide assembly for use in transferring containers along a path betweenprocessing stations of a packaging machine.

BACKGROUND OF THE INVENTION

Trends within the field of packaging machines point toward increasinglyhigh capacity machines intended for rapid, continuous filling andsealing of a very large number of identical or similar packagingcontainers, e.g., such as containers of the type intended for liquidcontents such as milk, juice, and the like. As these machines haveincreased in speed and decreased in size, the surrounding apparatus ofthese smaller more efficient packaging machines have had to be modifiedto accommodate these higher speeds.

Packaging machines are now known that integrate the various componentsnecessary to fill and seal a container into a single machine unit. Thispackaging process, generally stated, includes feeding blank cartons(blanks) into the machine, sealing the bottom of the cannons, fillingthe cartons with the desired contents, sealing the tops of the cartons,and then off loading the filled containers for shipping.

Packaging machines may employ endless rotating conveyors that allowvarious packaging processes to be performed repeatedly as the conveyortransports the cannons between a plurality of processing stations. Theseendless rotating conveyors include a plurality of carriers that arelocated around a conveyor loop. The carriers accept individual cannonblanks that are continuously fed onto the machine by means of aninfeeder, and convey them along a processing path to subsequent sealingand filling processing stations.

Increased throughput and decreased size requirements for packagingmachines have increased the demands that are placed on the endless beltconveyors that are employed. The increased speed and decreased size ofthese conveyors increases the forces on the individual components of theconveyor assembly. The stresses on these components tend to causeincreased component wear which, in turn, leads to frequent maintenanceand a corresponding decrease in the reliability of the machine. This isparticularly true along the arcuate portions of the track where themoment forces are larger than on the linear portion.

SUMMARY OF THE INVENTION

A conveyor system is set forth that includes a track having a generallylinear section and a generally curved section. The track furtherincludes a guide channel having sidewalls that engage a guide memberthat is in fixed positional alignment, for example, with a carrierand/or belt. The guide member engages the sidewalls of the guide channelto facilitate guided movement of the carrier and/or belt along thetrack. The guide member includes a linear portion that is engaged by thetrack when the guide member is disposed along the linear section of thetrack while being generally disengaged from the is engaged by the trackwhen the guide member is disposed along the curved section of the track.The guide member further includes a curved section that engages thesidewalls of the guide channel when the guide member is disposed alongthe curved section of the track. The radius of curvature of the curvedportion of the guide member generally coincides with the radius ofcurvature of the track about a curved portion of the track.

In accordance with one embodiment of the system, the system includesboth upper and lower oval-shaped tracks having guide channels withsidewalls that engage upper and lower guide members that are directlyaffixed to the rear of respective individual carriers. The carriers andguide members are disposed on opposite sides of an endless belt which,in turn, is disposed about the outer periphery of the tracks.

In accordance with one embodiment of the tracks, the tracks may each becomprised of an upper and lower portion. Each of the upper and lowerportions have an inner rail and an outer rail, the inner and outer railsbeing disposed on opposite sides of a respective guide channel portion.The upper portion and lower portion are joined to define the guidechannel of the track.

In accordance with one manner of operation of the disclosed conveyorsystem, the upper portion of the track engages the curved portion of theguide member when the carrier is disposed along the curved section ofthe track. At that point, the sidewalls of the guide channel portion ofthe lower portion of the track are generally disengaged from the linearportion of the guide member when the guide member is disposed along thecurved section of the track. When the guide member is disposed along thelinear portion of the track, the sidewalls of the guide channel portionof the lower portion of the track engages the linear portion of theguide member.

Several conveyor drive mechanisms are contemplated for use with theoval-shaped configuration. In accordance with one type of drivemechanism, a pair of drive wheels are disposed at opposite curved endsof the tracks. The drive wheels frictionally engage the rear surface ofthe endless belt and drive the belt, carriers, and guides about thetracks.

In accordance with a further type of drive mechanism, a pair of drivewheels are disposed at opposite curved ends of the tracks. The drivewheels include a plurality of uniformly spaced drive grooves. The drivegrooves engage drive lugs that may, for example, be affixed to thecarriers. For example, each carrier may include upper and lower guidemembers disposed respectively at the upper and lower portions of thecarrier. A drive lug may extend between and connect the upper and lowerguide members.

The foregoing conveyor system construction provides an endless rotatingconveyor that minimizes the force and wear exerted on the conveyor beltand the wear components thus prolonging the lifespan of the system andreducing its mean time between failures. The construction furtherprovides a conveyor system for a machine, such as a packaging machine,wherein the container carrier is affixed to the conveyor band on theopposite side of the wear parts, such as the guides and tracks, toprevent contamination of the containers on the carriers.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of an endless loopconveyor system illustrating its components, including a plurality ofcarriers holding cannon blanks.

FIGS. 2A-E illustrate one manner in which the ends of the conveyor beltmay be joined.

FIG. 3 is a perspective view of a carrier and its respective conveyorguide members.

FIG. 4 is a perspective view of a segment of the top and bottom portionsof a track.

FIG. 5 is a top view of a segment of the bottom portion of the track.

FIG. 6 is a top view of a segment of the top portion of the track.

FIG. 7 is perspective view of a conveyor guide member.

FIG. 8 is a view of the conveyor guide of FIG. 7 as viewed from theinside of the band.

FIG. 9 is a cross-sectional view of the conveyor guide member positionedin a linear section of the track as taken along the lines 9--9 in FIG.1.

FIG. 10 is a cross-sectional view of the conveyor guide memberpositioned in the curved portion of the track as taken along the lines11--11 in FIG. 1.

FIG. 11 is a cross-sectional view of the conveyor guide member along thelines 11--11 in FIG. 7.

FIG. 12 is a perspective view of one embodiment of a drive wheel fordriving the conveyor system illustrated in FIG. 1.

FIG. 13 is a perspective view of another embodiment of a drive wheel fordriving the conveyor system illustrated in FIG. 1.

FIG. 14 is a perspective view of a positive drive lug disposed betweenthe upper and lower conveyor guide members for use with the drive wheelof FIG. 13.

DETAILED DESCRIPTION OF THE DRAWINGS

A conveyor assembly 20 is illustrated in FIG. 1. Such a conveyorassembly 20 is suitable for use, for example, in a packaging machinesuch as the one disclosed in U.S. Ser. No. 08/190,546, filed Feb. 2,1994, (TPR-940) which is hereby incorporated by reference. The conveyorassembly 20 may be used to transfer carton blanks 30 along a generallyoval processing path in which the carton blanks 30 are sealed and/orfilled.

The conveyor assembly 20, as illustrated in the embodiment shown in FIG.1, is of an endless loop type and includes a plurality of carriers 40for holding canon blanks 30, a conveyor band 50, an upper track 60, alower track 70, a plurality of upper guide members 80 disposed withinthe upper track 60, a plurality of lower guide members 90 disposedwithin the lower track 70, and two drive wheels 100.

The upper and lower tracks 60 and 70 of the illustrated embodiment areof a generally oval shape and include linear sections 110 and curved endsections 120. The upper and lower tracks 60 and 70 are disposed parallelto one another. An endless band 50 extends about the outer periphery ofthe tracks 60 and 70, the ends of the band being joined, for example, inthe manner illustrated in FIGS. 2A-E.

As illustrated, the ends 121 of the band 50 are joined at a splicingsection 122. Each end 121 has a plurality of conical apertures 122which, as illustrated in FIG. 2D, overlie one another when the belt ends121 are fastened to one another with, for example, a bolt 123, washer124, and nut 125. By joining the band ends in the illustrated manner,the joined sections of the band remain relatively flat and do notexhibit the overlapped protrusions characteristic of other such joints.

As shown in FIG. 3, each carrier 40 has a pair of projecting arms 130that extend generally perpendicular from the band 50, a carrier back 140that is aligned generally parallel to the band 50, and a rear supportbar 150 that rests on the band 50' and separates the carrier back 140from the band 50. The projecting arms 130 are spaced apart to form acompartment therebetween for accommodating the packaging containerblanks 30. The projecting arms 130 each have a support 160 located atthe outer most portion of the arms. The supports 160 extend toward oneanother for gripping the outwardly facing corners of the packagingcannons. Each carrier 40 is rigidly attached to the conveyor band 50 bybolts 170, screws, or the like which extend through the carrier back140, the rear support bar 150, the band 50, and into the conveyor guidemembers 80,90. The carriers 40 are separated from the wear parts (here,the tracks 60,70 and the guide members 80,90) by the band 50 thusreducing the chances for contamination of the contents of the cannonblanks 30 carded by the carrier 40. Alternatively, the carriers 40 cancomprise T-shaped arms that are spaced uniformly around the band 50 suchthat the front of one arm and the rear of the next arm form a spacetherebetween for accommodating the packaging container blanks 30. Othercarrier types are also suitable for use with the illustrated system.

Each carrier 40 is in fixed positional alignment with a guide member 80positioned in the upper track 60 and a guide member 90 positioned in thelower track 70. For example, the guide members 80 and 90 may be rigidlyattached to the rear of the respective upper and lower portions of thecarrier 40. The upper and lower tracks 60 and 70 define guide channels180 in which the guide members 80 and 90 are disposed to facilitateguided movement of the guide members 80, 90 about the tracks.

FIGS. 4-6 illustrate the components that comprise the upper and lowertracks 60 and 70. For purposes of convenience only, the portion of trackshown in FIGS. 4, 5, and 6 will be referred to as the upper track 60.All references to the structure and components of the upper track 60,however, are equally applicable to the lower track 70, as they may, ifdesired, be identically constructed, differing only in their respectivelocations.

The upper track 60, has an upper portion 190 and a lower portion 200and, for example, may be constructed from stainless steel or the like.The upper portion 190 has linear sections 210 and an arcuate section220. The upper portion of track 60 also includes an inner rail 230 andan outer rail 240 that define a guide channel portion 250.Correspondingly, the lower portion 200 of track 60 has linear sections260, an arcuate section 270, and an inner rail 280 and outer rail 290that define a lower guide channel portion 300.

The upper track 60 is assembled by attaching the upper portion 190 tothe lower portion 200 such that the linear sections 210 and the arcuatesection 220 of the upper portion 190 of track 60 overlie the linearsections 260 and the arcuate section 270 of the lower portion 200 oftrack 60. The upper and lower portions of track 190,200 are affixed toeach other, for example by bolts, screws, or the like. When joined, theguide channel portions 250 and 300 are aligned to form the completeguide channel 180 (FIG. 3).

As shown in FIGS. 5 and 6, the guide channel portion 250 of linearsections 210 of the upper portion 190 of track 60 and the guide channelportions 300 of the linear sections 260 of the lower portion 200 oftrack 60 have the same widths, while the arcuate sections 220 and 270have different widths. The outer rail 240 of the lower portion 200 oftrack 60 decreases in width around the arcuate section 270 so that thelower guide channel portion 300 of the lower portion 200 of track 60 iswider around the arcuate section 270 than it is through its linearsections 260. The outer rail 290 of the upper portion 190 of track 60has the same width around the arcuate section 220 as it does in thelinear sections 210. Thus, the guide channel portion 250 has the samewidth throughout the entire upper portion of track 60. Alternatively,the guide channel portion 250 may be, for example, wider along linearsections 210 that is at the curved section 220.

As may readily be recognized, the upper portion 190 of track 60 and thelower portion 200 of track 60 can be inverted without detriment to theoperation of the conveyor assembly 20. A corresponding inversion of theguide members 80 would also be required in such an instance.

FIGS. 7-11 illustrate one embodiment of a guide member 80 suitable foruse in the presently described conveyor assembly 20. The guide members80, for example, may be manufactured from a polymer such as ultra highmolecular weight polyethylene (UHMW). As shown in FIG. 1, an upper guidemember 80 and lower guide member 90 are attached to each carrier 40 atrespective upper and lower portions thereof The guide members 80,90 maybe of identical size, shape, and structure. Each guide member 80,90 sitsin the respective guide channel 180 formed in the completed trackassemblies 60,70. Each guide member 80,90 has an upper portion 3 10, alower portion 320, a neck 330, and a cavity 340.

The lower portion 320 of the guide 80 has a generally fiat inner surface345 and a generally flat outer surface 350. The upper portion 310 of theguide 80 has a concave inner surface 360 and a convex outer surface 380so as to generally conform to the radius of the guide channel of thearcuate portion 220 of upper portion 190 of the track 60.

The neck 330 protrudes from the outer surface of the guide member 80through a gap between outer rails 240,290 and into contact with thebackside of the conveyor band 50. The guide member 80 is attached to therear support bar 150 of the respective carrier 140 by means of a bolt,screw of the like 390 that extends through the band 50 to rigidly attachthe carrier 140 to the guide member 80. When a bolt fastener is used,the end of the bolt 390 and a securing nut 395 rest in the cavity 340,such that neither the bolt 390 nor nut 395 will not contact the track 60as the guide members 80 travel trough the guide channel 180.

As shown in FIGS. 9 and 10, the guide member 80 rests in guide channel180. FIG. 9 is a cross-sectional view illustrating a guide member 80 asit travels through the linear section 110 of the upper track assembly60. While the guide member 80 is traveling through the linear section110 of the upper track 60, the inner and outer rails 280 and 290 of thelower track portion 200 enact as guides for the guidemember 80 byengaging the lower section 320 of the guide member 80. The upperportions of the guide member 80 need not be in contact with the upperportion 190 of the track 60 while the guide member 80 travels throughthe linear section 110 of the upper track 60.

FIG. 10 is a cross-sectional view of the track illustrating a guidemember 80 as it travels through the arcuate section 120 of the uppertrack assembly 60. As the guide members travel from the linear section110 of the upper track assembly 60, to the arcuate section 120 of theupper track assembly 60, inertia forces urge the convex surface of theupper section 310 of the guide member 80 against the outer rail 240 ofthe track 60. The convex outer surface of the guide member 80 may alsocontact the outer rail 240 of the upper portion 190 of the track 60. Inthe illustrated embodiment, the radius of the concave inner surfaceconforms to the radius of the inner rail 230 of the upper portion 190 ofthe track 60 and the radius of the convex outer surface conforms to theradius of the outer rail 240 of the upper portion 190 of track 60.

Since the lower guide channel portion 300 widens around its arcuateportion 270, the lower section of the guide member 80 is, for example,disengaged from contact with the inner and outer rails 280 and 290 asthe guide member 80 travels around the arcuate portion 120 of the track60. The upper section 310 of the guide member 80 thus functions, throughengagement with the track 60, as the principal guide for movement aboutthe curved sections of the track 60.

The guide members 80,90 facilitate transfer of the moment forces of thecarriers 140 to the tracks 60,70 instead of to the band 50. The wear onthe band 50 is thus reduced, providing the potential to increase itslongevity and mean time between failures.

It should be understood that the orientation of the guide members can bechanged such that the lower portion of the guide has a concave innersurface and a convex outer surface, and the upper portion of the guidehas a flat inner surface and a flat outer surface. However, if thisorientation is to be utilized, the orientation of the upper and lowerportions of the track should also be reversed.

Several different drive mechanisms are suitable for use in theillustrated conveyor assembly 20. Two such drive mechanisms areillustrated in FIGS. 12-14.

FIG. 12 illustrates a drive wheel 100 in accordance with one drivemechanism embodiment. The drive wheel 100 is a friction wheel that, forexample, may be driven by a high speed, low torque servo motor. Thewheels 100 frictionally engage the rear portion of the band 50 and drivethe band 50 to move the carriers 40 and guide members 80, 90 around thetracks 60,70. Alternatively, an electric motor or the like may be usedto drive the wheels 100. If a low torque servo motor is employed, agearing mechanism may be included to increase the torque applied to thedrive wheels 100.

FIG. 13 illustrates another embodiment of a drive wheel suitable for usein the illustrated conveyor assembly 20. The drive wheel 100 includes aplurality .of uniformly spaced grooves 410 along the outer surface ofthe wheel 100. The drive wheels 100 may, for example, be driven by ahigh speed, low torque motor (not shown) with a gear reducer to increasethe applied torque.

FIG. 14 illustrates the manner in which the drive wheel 100 may engagethe other portions of the conveyor assembly 20 to drive the carriers 40along the processing path. As illustrated, the guide members 80 and 90associated with, for example, each carrier 40 are connected to eachother through the use of a positive drive lug 420 so that the carriers140 can be driven by the lug 420 as opposed to frictional forces betweenthe wheels 100 and the backside of the band 50. The drive lug connectedto the neck 330 of the upper guide member 80 at a first end 430, and tothe neck 330 of the lower guide member 90 at a second end 440. The lug420 is affixed to the guide members 80,90, for example, by bolts 36which extend from the respective carrier 140, through the band 50,through the lug 420 before being affixed by a nut in the cavity of therespective guide member 80,90. As the lugs 420 are located against therearside of the band 50, the grooves 410 in the wheel 100, which areuniformly spaced about the wheel 100 to coincide with the distancebetween each lug 420, engage each lug to drive the carriers 140 aroundthe conveyor system 20.

While preferred embodiments of the invention have been describedhereinabove, those of ordinary skill in the art will recognize that theembodiments may be modified and altered without departing from thecentral spirit and scope of the invention. Thus, the preferredembodiments described hereinabove are to be considered in all respectsas illustrative and not restrictive, the scope of the invention beingindicated by the appended claims rather than by the foregoingdescription. Therefore, all changes and modifications which come withinthe meaning and range of equivalency of the claims are intended to beembraced herein.

We claim as our invention:
 1. A method for conveying a container along atrack having a linear portion and a curved portion, the track having achannel, the channel being linear in the linear portion of the track andcurved in the curved portion of the track, the method comprising thesteps of:providing a carrier supporting the container; providing a guidemember in fixed positional alignment with the carrier and engaging thechannel of the track; moving the carrier and guide member along thechannel of the track; guiding the guide member within the channel alongthe linear portion of the track with a generally linear portion of theguide member; guiding the guide member along the curved portion of thetrack with a generally curved portion of the guide member.
 2. A methodfor conveying a container along a track having a linear portion and acurved portion, the method comprising the steps of:providing a carriersupporting the container; providing a guide member in fixed positionalalignment with the carrier and engaging the track; moving the carrierand guide member along the track; guiding the guide member along thelinear portion of the track with a first portion of the guide memberspecifically adapted for engagement with the linear portion of thetrack; guiding the guide member along the curved portion of the trackwith a second portion of the guide member specifically adapted forengagement with the curved portion of the track.
 3. A method forconveying a container along a track having a linear portion and a curvedportion, the track having a channel, the channel being linear in thelinear portion of the track and curved in the curved portion of thetrack, the method comprising the steps of:providing a carrier supportingthe container; providing a guide member in fixed positional alignmentwith the carrier and engaging the channel of the track; moving thecarrier and guide member along the channel of the track; maintaining theguide member within the linear channel as the carrier and guide memberare moved along the track by causing engagement between sidewalls of thelinear channel and a generally linear portion of the guide member;maintaining the guide member within the curved channel as the carrierand guide member are moved along the track by causing engagement betweensidewalls of the curved channel and a generally curved portion of theguide member;